/*
 * (C) Copyright 2005- ECMWF.
 *
 * This software is licensed under the terms of the Apache Licence Version 2.0
 * which can be obtained at http://www.apache.org/licenses/LICENSE-2.0.
 *
 * In applying this licence, ECMWF does not waive the privileges and immunities granted to it by
 * virtue of its status as an intergovernmental organisation nor does it submit to any jurisdiction.
 */

/*
 * C Implementation: grib_clone
 *
 * Description: How to create a new GRIB message by cloning
 *              an existing message.
 *
 */
#include <stdio.h>
#include "eccodes.h"

static void usage(const char* app)
{
    fprintf(stderr, "Usage is: %s input_file ouput_file\n", app);
}

int sfx_grib_clone()
{
    int err = 0;

    FILE* in  = NULL;
    FILE* out = NULL;

    // char* infile = "D:\\temp\\era5-levels-members.grib";
    char* infile = "D:\\temp\\1.grib";
    char* oufile = "d:\\temp\\out.grib";

    in  = fopen(infile, "rb");
    out = fopen(oufile, "wb");

    if (!in || !out) {
        perror("ERROR: unable to open files");
        fclose(out);
        fclose(in);
        return 1;
    }

    codes_handle* source_handle = NULL;
    const void* buffer          = NULL;
    size_t size                 = 0;
    int cnt                     = 0;

    /* loop over the messages in the source grib and clone them */
    while ((source_handle = codes_handle_new_from_file(0, in, PRODUCT_GRIB, &err)) != NULL) {
        //
        cnt++;
        codes_handle* clone_handle = codes_handle_clone(source_handle);

        if (clone_handle == NULL) {
            perror("ERROR: could not clone field");
            return 1;
        }

        // ---------------------------------------------------------------
        // This is the place where you may wish to modify the clone
        // e.g.
        //    CODES_CHECK(codes_set_long(clone_handle, "centre", 250),0);
        // ---------------------------------------------------------------

        // get the coded message in a buffer
        CODES_CHECK(codes_get_message(clone_handle, &buffer, &size), 0);

        printf("message %d: size = %zd\n", cnt, size);

        // write the buffer to a file
        if (fwrite(buffer, 1, size, out) != size) {
            perror(oufile);
            return 1;
        }
        codes_handle_delete(clone_handle);
        codes_handle_delete(source_handle);
    }

    fclose(out);
    fclose(in);

    return 0;
}
